On April 19, 1993, federal agents stormed the compound on a hill called Mount Carmel, looking for illegal weapons they believed were held by a religious group that called itself the Branch Davidians.

They had initially tried to gain access to the cult's headquarters 51 days earlier, but were rebuffed when the members opened fire on officers. On April 19, FBI agents and officers from the Bureau of Alcohol, Tobacco and Firearms went to the compound again.

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Members of the group, which were a break-off sect of the Seventh Day Adventist Church, then set fires in the compound. They had been in Waco awaiting the second coming of Christ.

The scene in West, Texas, today is very different, with rescue workers trying to comb through the wreckage of a fertilizer plant that exploded and caught fire Wednesday. Authorities are still searching for survivors and missing people amid buildings that have been torn open or flattened.

Officials said they fear five to 15 people could be dead, although the mayor said today that as many as 40 people are unaccounted for.

"It ranges from broken windows to complete devastation," Waco Police Department Sgt. William Swanton said at a news conference today. "There are homes that are no longer homes."

At some buildings, "walls were ripped off, roofs were peeled back," the sergeant said.

The fire and explosion prompted widespread evacuations and sent more than 160 injured people to hospitals.